Advance Paris WTX-Tubes Bluetooth Receiver

The Advance Paris WTX-Tubes is a Bluetooth receiver with a genuine tube output stage: two Raytheon 5703 subminiature tubes in Class A operation refine the signal before it reaches the amplifier.

In principle, it does the same thing as a bargain-bin Bluetooth dongle – except you can hear the difference. Instead of a plastic stick, a solid metal chassis sits on the shelf, with two tubes glowing behind its tinted viewing window.

Why the WTX-Tubes?

Bluetooth has a reputation as a compromise – the WTX-Tubes disagrees. After reception (Bluetooth 5.0 with aptX HD, Qualcomm QCC controller), a Wolfson WM8740 converts the signal at up to 24 bit / 192 kHz before it runs through the two tubes. That convinced the specialist press too: MODERNHIFI awarded 9.2 out of 10 points in its test dated 29.07.2021, praising the "detailed and warm sound reproduction".

What you get

A metal chassis 13 centimetres wide and a good half a kilo in weight – it feels less like an accessory than a proper device. Connection is via RCA to any amplifier with a free line input; alternatively, coaxial and optical digital outputs are available if you'd rather leave the conversion to your own DAC. Your smartphone pairs in seconds: Android devices use aptX or aptX HD, iPhones AAC – both sound clean. What you play is entirely up to you, no streaming subscription required. Power comes from an external 5-volt power supply with active noise suppression.

Who is the WTX-Tubes suited for?

To put it plainly: if you want Wi-Fi streaming, apps and multiroom, go for its sister model, the WTX-StreamTubes – the WTX-Tubes handles Bluetooth exclusively. You'll also look in vain for a volume control: the RCA output delivers a fixed level, volume is set at the amplifier, and there's no headphone output. But if you want to give your system wireless access with character instead of a plastic dongle, you've come to the right place.

Our verdict

The WTX-Tubes turns plain Bluetooth into a small sonic event – and looks like a mini tube amplifier while doing it. Whether its warm fundamental tone suits your speakers is something we're happy to discuss beforehand at HD Zürisee in Wädenswil: 044 680 22 00 or WhatsApp 076 534 22 00 (text only, no calls).

Technical Data

• Type: Bluetooth receiver with tube output stage
• Tubes: 2× Raytheon 5703 (subminiature, Class A)
• Bluetooth: Version 5.0, Qualcomm QCC controller
• Codecs: aptX HD, aptX, AAC, SBC
• Range: approx. 10 m in open space
• D/A converter: Wolfson WM8740, 24 bit / 192 kHz, 117 dB dynamic range
• Processor: tri-core (2× 32 bit + 1× 120 MHz)
• Analogue output: RCA stereo via the tube stage
• Digital outputs: coaxial (S/PDIF) and optical (Toslink)
• Output level: fixed (line level), no volume control on the unit
• Headphone output: not present
• Chassis: metal, tinted viewing window onto the tubes
• Power supply: external power supply 5 V / 1 A with active noise suppression
• Dimensions (W×H×D): 13 × 4.2 × 11 cm
• Weight: 532 g
• Included: WTX-Tubes, external power supply, user manual

Frequently Asked Questions

Which smartphones does the WTX-Tubes work with?

With all Bluetooth devices. SBC and AAC ensure universal compatibility, and most Android smartphones additionally provide aptX or aptX HD for full resolution. iPhones transmit via AAC – the receiver still sounds clean and detailed with that, just not in 24 bit.

How do I connect the WTX-Tubes?

In analogue via RCA to a free line input on your amplifier. That's the standard route, where the tube stage contributes its sound. Alternatively, coaxial and optical digital outputs are available if you prefer an external DAC – though in that case the tubes are bypassed. Power is supplied by the included power supply.

Does the WTX-Tubes have a headphone output or volume control?

No, neither. The WTX-Tubes outputs a fixed line level via RCA and leaves volume and headphones to the amplifier downstream. It's designed as a pure source, not a preamp. It should therefore explicitly not be connected directly to a power amp – an amplifier with level control needs to sit in between.

WTX-Tubes or WTX-StreamTubes – which suits me?

The WTX-Tubes is the pure Bluetooth solution: pair your smartphone and you're done. The WTX-StreamTubes additionally offers streaming over Wi-Fi and Ethernet with Spotify, Qobuz and the like built right into the unit. Same tubes, different feature set – we're happy to help you figure out which one suits your everyday use over the phone.

Why buy the WTX-Tubes from HD Zürisee?

Because with us, experience advises you, not a spec sheet. We know this receiver's strengths and limits and will tell you honestly whether it suits your system and your smartphone. Our technician Mauri helps with setup, and we handle the warranty cleanly as an authorised dealer.

Goes well with

An integrated amplifier with a free line input, other streamers as an alternative with a network connection – or more from Advance Paris.